Local mail server as an intermediary between the hoster's mail server?

Question

Mail server

Good afternoon!
The hoster has a mail server, there are no steering wheels from it at all (only creating mailboxes and resetting passwords), I want a local one and all the charms of domain authentication, prohibition of attachments, etc. with it.
Is it possible that the local server I raised would be like an intermediary between the host server, i.e. so that he would go to the hoster's server and pick up mail from mailboxes to his mailboxes (server domain names are different, but user logins are the same) and users have already taken it from him.
If there is, tell me what it's called in which direction to dig.
PS: hoster server is postfix, my local zimbra

Answer 1

There is no such thing as a simple mail server, usually a combination of an SMTP server, a POP3 server, and an IMAP server. In Zimbra, by the way, it seems like a postfix as SMTP.
The hoster's mail server receives mail via SMTP and arranges it into mailboxes, respectively, you need to pick up mail from your hoster using the POP3 or IMAP protocol and each user should do this separately (like Zimbra has the ability for the user to pick up mail from external mailboxes via IMAP, but configures this is everyone at home)
Option number two, you register your Zimbra for your domain in the MX records of the domain and take all the mail for the domain on yourself and drive mailboxes yourself. But you must have a static IP

Answer 2

I didn't quite understand what you want.
In my experience, there was setting up fetchmail, officemailserver, kerio, sendmail and distribution to local mailboxes.
By the way, the provider had a common mailbox for everyone, the sorter then sorted it into separate boxes and copied it to the director.
As for the local server, you set up the forwarding server in the local area. He will deal with spamming too large letters, internal correspondence and forwarding to an upstream server.
There are enough mailforward articles on the Internet, for example, for your system https://www.zimbra.com/desktop7/help/en_US/Userspe...

Answer 3

I thought about the same thing, but postponed it for an indefinite period
Problems:
1) The hoster limits resources - the number of connections, the number of letters (especially sending) - you have to pay
2) There is a mail collector in zimbra - it seems to be, but you won’t run it every minute - see paragraph 1. those delays in receiving emails.
3) setting up zimbra - each client will have to manually prescribe the POP connector. if 1-20 users are still normal, but if 1000.
4) Let's say there is a collector, but send it - I got up on this))). Laziness))). The idea is to play with MX records. You have 2 mail servers:
the 1st at the hoster - it has a higher priority - everything falls to it
The 2nd one you have - with a white IP (required) - the priority is lower, but it is also registered in DNS and it sends from your domain. The mail must go.
I think the issue is resolved.
Go to the hoster and ask him the same question - if normal, they will immediately issue an invoice))) and everything will be set up for $ 10,000 (just kidding)